Cooking plate

ABSTRACT

A hotplate, such as a plate of vitreous ceramic, intended to equip a cooker having at least one gas burner, includes a raised zone intended to cover the gas burner. The raised zone includes orifices.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a hotplate intended to equip a cooker such as ahob comprising at least one gas burner. According to the invention, thehotplate is made of vitreous ceramic or of another material resistant tohigh temperatures and having a low coefficient of expansion.

In order to simplify its explanation, the invention will be describedwith reference to vitreous ceramic plates. Such an explanation of theinvention must not in any way lead to the invention being interpreted asbeing restricted to this material.

2. Description of the Related Art

Gas cookers or hobs with gas burners, the top plate being made ofvitreous ceramic, are known in the prior art.

Such gas burners are, in the usual way, arranged in a structure, usuallymade of metal, known as the carcass and covered with a vitreous ceramicplate equipped with a surround which closes the structure.

The objective in designing these cookers has been for them to besubstitutes for more conventional cookers usually consisting of anenamelled sheet on which the gas burners are positioned and of a metalgrating which covers them.

This substitution has allowed this type of cooker to reach new aestheticheights. Furthermore, the use of a vitreous ceramic plate makes cleaningeasier.

Thus, document EP-A 879 797, for example, discloses a device formounting gas burners in holes made in a vitreous ceramic plate formingthe upper part of a cooker.

Document DE-U 298 05 620 describes such a cooker and, more particularly,mounting means that allow the gas burners to be attached to the vitreousceramic plate with seals to make the connection between the vitreousceramic plate and the gas burner.

Again, document W097/00407 describes such a cooker in which the gasburners are surrounded by elements to support cooking utensils used forcooking food.

Patent FR-B-2 735 562 describes cookers comprising a vitreous ceramicplate supporting the gas burners and also fulfilling the function ofsupporting the cooking utensils.

It is also known practice for such cookers to be produced in which thecooking utensils are supported by the upper part of the gas burner.

These various types of embodiment of cooker have gas burners associatedwith a vitreous ceramic plate which forms the main upper part of thecooker and have in common the ease of cleaning the upper surface, thelatter being formed of a vitreous ceramic plate. The only zones of thecooker which remain difficult for the user in terms of upkeep are thezones containing the gas burners; specifically, these burners have to beat least partially dismantled then refitted in order to be cleanedsatisfactorily.

SUMMARY OF THE INVENTION

The inventors have therefore set themselves the task of offering thepossibility of providing a cooker comprising at least one gas burner andthe upper part of which is formed of a hotplate, such as a vitreousceramic plate, for which cleaning is made even simpler than is allowedby the currently known products.

This objective has been achieved, according to the invention, by ahotplate, such as a plate of vitreous ceramic, intended to equip acooker comprising at least one gas burner, the said vitreous ceramichotplate comprising a zone intended to cover the gas burner and the saidzone having orifices, designed, in particular, to form an air inlet tothe gas burner and to allow the flames out.

According to the invention, the gas burner is completely concealed bythe hotplate and is therefore invisible to the user; such a designprovides a twofold simplification to the cleaning of the cooker.Specifically, first of all, the gas burner, which is concealed, isprotected from mess and therefore less likely to become soiled.Furthermore, when the user cleans the visible part of the cooker, he hassimply to clean the hotplate, this considerably simplifying theoperation by comparison with the cleaning of the cookers currentlyavailable.

Furthermore, such a design of the cooker gives a new aestheticappearance which follows the recent trends, namely a clean look with theleast possible number of visible functional elements. Specifically, thecooker which has a gas burner shows only the orifices which, as alreadystated, are designed on the one hand to allow air to the burner and, onthe other hand, to allow flames to be formed and to exit at the uppersurface of the hotplate so as to heat the cooking utensils.

Advantageously according to the invention, the orifices are holes and/orslots. Such orifices may be made by techniques known to those skilled inthe art such as, in particular, laser cutting or waterjet cuttingtechniques. According to the various types of design, the orifices mayeither act simultaneously as air inlets and as flame outlets, or besplit into two categories, the first forming the air inlet and thesecond the flame outlet.

According to a preferred embodiment of the invention, the hotplate iscapable directly, that is to say without intermediate elements, ofsupporting cooking vessels or utensils over the gas burner.

A first variant of the invention makes provision for the zone coveringthe gas burner to be capable of contributing to supporting the cookingutensils. In this variant, this zone covering the gas burner may have atleast one raised part on which a cooking utensil can rest, at least inpart.

A second variant makes provision for the hotplate to comprise bossesdistributed at the periphery of the zone covering the gas burner. Thus,cooking utensils can rest on these bosses of which, for the cookingutensils to be properly stable, there are preferably at least three.

According to a third variant, the invention makes provision for acombination of the first two variants, namely for the zone covering thegas burner to be designed to support cooking utensils in associationwith bosses distributed at its periphery.

A first design of the invention consists in producing the hotplate in atleast two separate elements, a first, essentially flat, elementcomprising at least one opening, in which the gas burner will be housed,and a second element intended to close off the said opening and formingat least part of the zone covering the gas burner. The second elementmay have the shape of a cap, the geometry of which remains arbitrary andchosen particularly for aesthetic considerations; the overall shape ofthis element may, for example, be circular, parallelepipidal,star-shaped, etc. This cap may be formed of an essentially flat upperpart which is raised with respect to the plane of the first element,able in particular to at least contribute to supporting the cookingutensils, and of vertical or slightly inclined side walls. The upperpart of the cap which may contribute to supporting the cooking utensilsmay be either smooth or may have a relief making it possible, forexample, to avoid slippage.

As a preference, the orifices are formed in the second element which mayhave the shape of a cap and more particularly in the side walls thereof.

This assembly formed by the two elements that make up the hotplate needsto be correctly sealed where the two elements meet so that water, forexample used to clean the visible surface of the hotplate, cannotpenetrate inside. Furthermore, from a hygienic point of view, as such aplate is used for the preparation of food, it is necessary to avoid anyrisk of soiling so that germs will not proliferate. Provision is thusadvantageously made for the two elements to be assembled via a seal, forexample made of silicone, placed on the first, essentially flat,element, the second element coming into contact with this seal which iscrushed under the weight of the said second element, sealing thus beingachieved. Furthermore, one element may advantageously be fixed withrespect to the other simply under the weight of the second element, andby indexing the latter with respect to the first element. It is thuspossible to form a barrier, particularly against water, and as theattachment is simple, the two elements can be separated at any time formore intense cleaning and, in particular, to avoid the proliferation ofgerms at the seal.

According to a second preferred design of the invention, the hotplate isessentially flat and has at least one deformed zone which has theorifices and which covers the gas burner. Also as a preference, thedeformed zone represents, with respect to the main plane of the plate,at least one boss and/or one recess. This deformation of the plateadvantageously includes an essentially flat part raised up with respectto the main plane of the plate. Advantageously also, it has roughlyvertical or inclined side walls in which the orifices are made.

Like the second element in the case of the two-element embodiment, thedeformed zone may have an overall shape which is independent of itsfunction and which may be chosen arbitrarily. The upper part which mayadvantageously be flat and at least partially contribute to supportingcooking utensils, may be either smooth or have a relief. This embodimentof the invention made as a single element with at least one deformedzone can be achieved according to the teaching of document FR-B-2 735562.

Whatever the embodiment of the hotplate according to the invention, itis clear that the said hotplate, associated with a gas burner, nowleaves only orifices still showing. Specifically, according to theinvention, there is now no burner emerging through the plate andpossibly supported thereby, the burner being wholly located under thehotplate. A gas burner more particularly suited to this design is aburner with a high primary ventilation rate.

The inventors have also envisaged simplifying the gas burner by usingthe zone that covers it to form part of the combustion chamber thereof.Specifically, for example the deformed zone of the hotplate mayconstitute the upper part of the combustion chamber. It is alsopossible, according to another advantageous embodiment, for thisdeformed zone also to substitute for the part of the burner which hasorifices where the flames are formed, it being possible according tocertain embodiments of the invention for the said deformed zone toitself have orifices designed for the passage of the flames.

According to other embodiments, the inventors also make provision forelectrical heating elements such as radiant elements to be associatedwith this design, these other elements being inserted between the gasburner and the hotplate. According to such embodiments, the electricheating element may be fixed, for example, to the upper part of thecombustion chamber of the gas burner. This type of embodiment may allowelectrical heating to be substituted for gas heating, for example forwarming a dish.

The invention also makes provision for making hotplates designed toequip hybrid cookers, that is to say ones which may have gas ringsassociated with radiant electrical, halogen and/or induction rings. Forthis type of hotplate, the inventors advantageously envisage producingall the zones intended to cover a cooking ring in the same way, that isto say in accordance with what has just been described, so as to offer acooker with a uniform appearance.

BRIEF DESCRIPTION OF THE DRAWINGS

Other details and advantageous features of the invention will emergehereinafter from the description of one exemplary embodiment of theinvention with reference to FIGS. 1 and 2, which depict:

FIG. 1, a schematic perspective view of a vitreous ceramic plateproduced according to the invention,

FIG. 2, an enlarged view of part of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

To assist with their understanding, the figures are not to scale.

FIG. 1 depicts a vitreous ceramic plate 1 made as a single piece anddesigned to form four gas rings at the four locations 2 which are inrelief on the plate. The vitreous ceramic plate 1 also comprises fourholes 3 which are designed for the spindles of the gas burner controlsto pass through. The presence of the holes 3 and their location must notlead to the invention being interpreted in a restrictive way; they mayindeed not be present, for example when the controls are installedindependently of the plate or in the case of sensitive controls, andwhen they are present, their distribution may be different.

The four locations 2 are produced according to the technique taught bypatent FR-B-2 735 562 which describes a method for producing bosses bydeformation forming an integral part of the vitreous ceramic plate.

It is therefore apparent that, according to the invention, the vitreousceramic plate will wholly cover the gas burners, which are fitted in asupport carcass or surround not depicted in the figures, to form acooker. According to variants of the invention and as explainedhereinabove, it is possible to associate this type of vitreous ceramicplate with gas burners, the manufacture of which is simplified or atleast scaled down; specifically, it is possible to make provision for adeformed part 2 of the vitreous ceramic plate to constitute at least theupper part of the combustion chamber of the gas burner.

In the embodiment set out in the figures, the deformations 2 made havealso the function of supporting the cooking utensils such as saucepans.The diameters likely to contribute to supporting are designed to havediameters that vary from one location 2 to another, as is the case inmore conventional cookers; specifically, the diameters of the supportelements or, more precisely, the diameters of the gas burners, areusually designed with dimensions which vary on one and the same cookerso as to be suited to cooking utensils or saucepans of different sizes.Thus, the upper surfaces 4 of the deformations 2 intended to cover thegas burners have been made flat to offer stable support to utensils suchas saucepans. According to other embodiments, the surface of adeformation may itself have a more or less pronounced relief either toform a roughness and prevent slippage or to constitute point supportsbetween which the air or the combustion gases can flow under the bottomof the cooking utensil.

Better depicted in FIG. 2, which is an enlarged view of region A in FIG.1, the deformations 2 according to this embodiment of the inventionconsist of an upper part 4 and of a side part 5 which forms an inclinedplane. This inclined plane also has slots 6 distributed about theperiphery of the deformation 2. These slots 6 are produced after theplate has been deformed by any means known to those skilled in the art,such as waterjet cutting or laser cutting. The invention also makesprovision, according to other embodiment variants, for the orifices orslots 6 to be produced before the plate is deformed. These slots 6 aredesigned, on the one hand, to form the output orifices for the flamesand, on the other hand, to allow air to the gas burner. These slots 6,as far as flame outlet is concerned, are superposed on or substitutedfor, particularly when the vitreous ceramic plate constitutes the toppart of the combustion chamber, the flame outlet orifices of the burner.Specifically, and at least as far as appearances go, the flames, as faras an external observer, and particularly the user, is concerned,originate from these slots. This novel design of a cooker with gasburners therefore truly offers a new appearance, and does so also whenusing the burners because the flames seem to take shape on the vitreousceramic plate.

According to other embodiments, it is possible to separate the functionsof supplying air to the burner and of letting the flames out, forexample by forming two levels of orifices on the periphery of thedeformation 2. For example, it is possible to provide a lower levelconsisting of slots for the air inlet and an upper level allowing theflames out and consisting of holes also distributed around the entireperiphery.

It is also possible according to the invention to make provision for forall of these orifices 6 formed on the lateral part 5 of the deformations2 to have an internal shape, not depicted in the figures, for exampleprovided on the lower zone 7, which forms a barrier against the ingressof liquid into the gas burner. Such an internal shape may be a simpleinclined plane or a more complex shape defined particularly according tothe shape of the orifices 6, to their positions and to the inclinationof the side wall 5. This internal shape of the orifices 6 may beobtained directly during the stage of cutting the orifices 6, or bylater shaping.

Such an embodiment of the vitreous ceramic plate 1 according to theinvention therefore offers a surface consisting of a simple materialand, according to this embodiment, made of a single element which, asidefrom having an appearance which is novel for cookers with gas burners,will very advantageously allow the upkeep of such a device to besimplified by comparison with the products which currently exist.

As regards the upkeep or repair of the gas burners, and more generallyof all the elements located under the vitreous ceramic plate when thecooker is produced, the inventors have advantageously envisaged anassembly with the carcass which allows easy access to the burners; suchan assembly for example envisages a device of the hinge type whichallows the vitreous ceramic plate 1 to be lifted up completely withoutfully detaching it from the carcass and therefore without any problem ofrefitting or repositioning it. Such a device is naturally accompanied bysuitable seals around the entire periphery so as to provide sealing whenthe vitreous ceramic plate 1 is in the functional position.

The vitreous ceramic plate 1 depicted in the figures must not lead tothe invention being interpreted in a restrictive manner; specifically,the invention is aimed at any type of vitreous ceramic plate intended tocover at least one gas burner. Such a plate may therefore have onesingle location 2 or several depending on the cooker that is to beproduced, the four-location embodiment being merely one example.Furthermore, the vitreous ceramic plate may also be intended to cover,in addition to one or more gas burners, other types of cooking elementsuch as radiant electric, halogen and/or induction elements.

The inventors have also envisaged keeping such a vitreous ceramic plate1, that is to say one with four deformed locations 2, when, for example,two gas burners are associated with two radiant electric, halogen and/orinduction heating elements, possibly without forming the orifices overthe electrical elements. Such an embodiment makes it possible tomaintain a uniform overall appearance of the vitreous ceramic plate. Itis also possible to make such deformations 2 only over the gas burnersand to keep the plate flat when it covers electrical elements, toguarantee that the various zones can be recognized.

What is claimed is:
 1. A hotplate, for a cooker comprising at least onegas burner, comprising a substantially planar plate, wherein said platecomprises at least one zone in the form of at least one boss and/orrecess with respect to the main plane of said plate, positioned oversaid at least one burner, said zone being either a deformation of theplate or the plate and zone being formed of at least two parts which arecontinuous with one another, said zone having at least one orifice. 2.The hotplate according to claim 1, wherein the at least one orifice isat least one of slots and holes.
 3. The hotplate according to claim 1,wherein the plate is capable of directly supporting cooking vessels orutensils over the gas burner.
 4. The hotplate according to claim 3,wherein the zone covering the gas burner is capable of contributing tothe supporting of the cooking vessels or utensils.
 5. The hotplateaccording to claim 3, wherein said zone has bosses distributed at theperiphery of the zone covering the gas burner to at least contribute tothe supporting of the cooking vessels or utensils.
 6. The hotplateaccording to claim 1, wherein the hotplate comprises a first,substantially flat, element comprising an opening and a second elementintended to close off the said opening and forming at least part of thezone covering the gas burner.
 7. The hotplate according to claim 6,wherein the second element has the orifices.
 8. The hotplate accordingto claim 1, wherein said zone which has the orifices and which coversthe gas burner is deformed.
 9. The hotplate according to claim 8,wherein the deformed plate represents, with respect to the plane of theplate, at least one boss or recess.
 10. The hotplate according to claim8, wherein the zone has an essentially flat part which is raised withrespect to the plane of the plate.
 11. The hotplate according to claim8, wherein the zone has roughly vertical or inclined side walls in whichthe orifices are made.
 12. The hotplate according to claim 1, whereinthe zone covering the gas burner constitutes part of the gas burner. 13.A cooker comprising at least one gas burner, further comprising ahotplate comprising a substantially planar plate, wherein said platecomprises at least one zone in the form of at least one boss and/orrecess with respect to the main plane of said plate, positioned oversaid at least one burner, said zone being either a deformation of theplate or the plate and zone being formed of at least two parts which arecontinuous with one another, said zone having at least one orifice. 14.The cooker according to claim 13, further comprising at least oneradiant electrical, halogen and/or induction cooking element.
 15. Ahotplate for a cooker having at least one gas burner, wherein thehotplate comprises: a substantially planar plate; and a raised zonepositioned over said at least one burner, wherein said raised zone iselevated with respect to said substantially planar plate, and whereinsaid raised zone includes at least one orifice, the entirety of said atleast one orifice being elevated with respect to said substantiallyplanar plate.
 16. The hotplate according to claim 15, wherein saidraised zone comprises a boss and wherein said at least one orifice is inthe side wall of the boss.
 17. A cooker comprising: at least one gasburner; and a hotplate comprising a substantially planar plate and araised zone positioned over said at least one burner, wherein saidraised zone is elevated with respect to said substantially planar plate,and wherein said raised zone includes at least one orifice, the entiretyof said at least one orifice being elevated with respect to saidsubstantially planar plate.
 18. The cooker according to claim 17,wherein said raised zone comprises a boss and wherein said at least oneorifice is in the side wall of the boss.